1. Field of the Invention
The present invention relates to a method for decomposing or oxidizing dioxins and/or PCBs into unharmful substances. To be more specific, it relates to a method for effectively decomposing or oxidizing dioxins and/or co-planer PCBs(poly chlorinated biphenyls) contained in liquid.
2. Description of the Prior Art
Dioxins including co-planer PCBs are chemically stable and accumulate in nature year by year.
Even though many methods for decomposing dioxins contained in soil and in incinerated gas have been suggested, many difficulties have been remained for decomposing dioxins contained in liquid, since dioxins are presented in pico gram per litter (pg/liter) concentration in liquid.
An object of the present invention is to provide a simple method which can efficiently convert dioxins and/or PCBs contained in liquid into unharmful substances.
Another object of the present invention is to provide a simple method which can efficiently extract dioxins, PCBs and/or component containing thereof, from soil.
Further, another object of the present invention is to provide a method for cleaning the unit used for decomposing or oxidizing dioxins and/or PCBs contained in liquid.
First object of the present invention can be solved by a method comprising of; introducing a liquid containing dioxins and/or PCBs, and oxygen containing gas to a reactor in which a catalyst is charged, and conducting wet-oxidation reaction under liquid phase condition of the introduced liquid.
Second object of the present invention can be solved by a method comprising of; contacting soil and/or ash containing dioxins and/or PCBs with a liquid for extraction.
Third object of the present invention can be solved by a method comprising of; by introducing cleaning solution to the unit used for decomposing or oxidizing dioxins and/or PCBs and conducting cleaning operation under liquid phase condition.
Other objects, features and advantages of the present invention will become apparent from xe2x80x98the detailed description of the preferred embodiments of the invention xe2x80x99 to follow.